Hello Vincent,
Last, If I try InfinitePlane (referenced node), this is just a drawable,
so it getNormal() method always return me the same value... whatever be
the Dragger state. And I need a plane normal() in world coordinate...
That's just because the normal is in local coordinates. Transform it
with the accumulated local-to-world matrix. To transform a vector, you
need to multiply it by the inverse transpose of upper 3x3 part of the
transformation matrix, which in OSG can be done by pre-multiplying
instead of post-multiplying and using osg::Matrix::transform3x3, with
the inverse local-to-world, or the world-to-local.
inline osg::Vec3f transform_position(const osg::Vec3f& position,
const osg::Matrixd& localToWorld)
{
// v' = v * Mlw
osg::Vec3f transformed_position = position * localToWorld;
return transformed_position;
}
inline osg::Vec3f transform_normal(const osg::Vec3f& normal,
const osg::Matrixd& invLocalToWorld)
{
// Normal must be multiplied by the inverse of the transpose of the
// local-to-world matrix : (Mlw ^ -1) ^ t
// V' = M * V is the same as V' = V * M^t where M^t is the
// transpose of M.
// n' = n * (Mlw^-1)^t
osg::Vec3f transformed_normal =
osg::Matrix::transform3x3(invLocalToWorld, normal);
transformed_normal.normalize();
return transformed_normal;
}
J-S
--
______________________________________________________
Jean-Sebastien Guay jean-sebastien.g...@cm-labs.com
http://www.cm-labs.com/
http://whitestar02.webhop.org/
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